Extendable assembly for supporting sofa table

ABSTRACT

A sofa table is height adjustable and has a horizontal table top with all or a portion that can be raised in an upward direction laterally using a height extendable assembly. This capability will expand the use of the sofa table to serve the functions of an ordinary table that can be used for activities like writing or eating. The undercarriage includes an inclined adjustable assembly pivoted to the table top and the bottom of the leg frame assembly to enable sliding upwards and downwards movements. A controlling fixture is integrated into the adjustable assembly to lock the table top at the desired height level within its range of adjustment. A releasable angled lever is utilized to engage and disengage the locking mechanism is connected to the extendable assembly. A press on the lever will disengage the locking mechanism and while holding down the lever and with a lifting force applied simultaneously on the table top will allow the table top to elevate to the desired height within its range of adjustment.

RELATED APPLICATION

The present application is a continuation-in-part and claims priority from, U.S. application Ser. No. 10/849,851, filed May 21, 2004, which is a continuation-in-part of PCT/SG02/00253, filed Oct. 29, 2002 which claims priority from Malaysia PI 2001 5359, filed Nov. 23, 2001, the disclosures of which are hereby incorporated by reference herein in their entirety.

FIELD OF INVENTION

The present invention relates generally to a sofa table and more particularly to a sofa table having a top, part or all of which is adjustable as to height. In particular, this invention allows a sofa table to be used as dining table or writing table while sitting on an ordinary sofa.

BACKGROUND OF INVENTION

The limited space available in many town houses, as well as apartments requires the greatest advantage of the available space. In particular, it is desirable to use the same sofa table for dining in addition to serving its originally intended purpose like repository for books, magazines and the like. A sofa table is also used to place food and beverages either while watching television or receiving guests. It is known that conventional sofa table usually has a top at the same level as the sofa, therefore it is necessary to bend over to reach the dish and it is not only clumsy and not ergonomic but could also be a difficult task for people with physical limitations to reach a level so much lower than that to which one is used to.

It is the intention of this invention to address the above-mentioned limitation of a sofa table. Therefore, when it is needed, a part of the table top of the sofa table can be raised and converted to suit the needed height, for example one can enjoy a meal on the raised portion of the sofa table while sitting on the same sofa. Books, magazines and other things that are placed on the sofa table can be left alone untouched on the other portion of the sofa table. Upon completion of the meal, the raised portion of the table top can again be reposited back to its original place, the sofa table can be easily and swiftly transformed back to an ordinary sofa table.

SUMMARY OF INVENTION

It is therefore an object of the present invention to provide an extendable assembly to a sofa table that enables users to elevate the height of a portion of the sofa table and transform the sofa table into a table with higher top.

It is an object of the present invention to provide an adjustable mechanism to enable a portion of the sofa table to be raised to the desired height. It is a further object of the present invention to provide the necessary mechanism to engage and disengage the locking mechanism so that the sofa table can conveniently and shiftily be adjusted to a desired height. It is of also paramount important to ensure that the elevated sofa table is well supported and balanced in weight due to the variation in the gravity level for different portions of the table, in order to avoid the table being toppled.

According to one aspect of the invention, a sofa table includes a horizontal table top supported by a leg frame assembly and at least a portion of the table top being a height adjustable part. The table top portions and all its supporting members can be at any size or length joined rigidly by connection means to each other to form the sofa table. All parts could be of any materials, could be of plain or incorporated with any external design or crafting in order to improving its appearance for the purpose to attract buyer.

In one embodiment of the invention, an extendable support member has opposing first and second support ends, with at least one end pivotally connected to the adjustable section of the table top and another end pivotally connected to the leg frame assembly of the stationary table section leg means at the lower part of the said sofa table, acting like an inclined strut supporting load from the said adjustable section of the table top. The design and placement of the extendable assembly for supporting sofa table is essential in order to provide stability to the sofa table. In general, the pivoting location is at proximity whereby the means can provide the equilibrium support to the table top at any height. If more than one of such strut are needed to support heavy duty sofa table, these adjustable means can be pivoted at equidistance to share the load so that the table will be at all time in equilibrium state.

In one embodiment of the present invention, a height adjustable sofa table comprising a stationary strut member mounted in an inclined manner to a sofa table, wherein the bottom end of the stationary strut member is coupled to the bottom section of a leg member of the sofa table and the top end of the stationary strut member is coupled to the bottom surface of the top face of the sofa table. The stationary strut member has a hollow passage and a fixed wedge attached at a predetermined position in the passage. The fixed wedge is disposed such that an inclined surface is formed facing upwards. A movable shaft member is slidably coupled to the stationary strut member, wherein the top end of the movable shaft member is coupled to the bottom surface of the top face of the sofa table. The bottom surface of the movable shaft member is slidably mounted on the top surface of the stationary strut member.

In another embodiment of the present invention, a controlling fixture has a movable wedge positioned relatively at the bottom of the fixed wedge, wherein the movable wedge is disposed such that an inclined surface is formed facing downwards and engageable with the inclined surface of the fixed wedge. The movable wedge has a resilient gripper attached to a top surface thereof. The resilient gripper on the top surface faces towards and engages the bottom surface of the movable shaft member. The controlling feature is an elongate rod slidably mounted through a through bore formed at the fixed wedge, wherein the bottom portion of the elongate rod is fixedly mounted through a through hole formed at the movable wedge. A stopper is disposed at the bottom section of the stationary member and the stopper terminates the passage of the stationary member. A resilient means is attached at the bottom end of the stopper and attached at the top end to the movable wedge. An angled fixture is mounted to the top section of the opposing leg member. The angled fixture is arranged to actuate the elongate rod and move the movable wedge towards the stopper. When the elongate rod is actuated by the angled lever, the movable wedge is forced to move downwards and the resilient means is compressed and the resilient gripper is released from its engagement with the movable shaft member and allows the sliding of the movable shaft member that facilitates the adjustment of height of the adjustable tabletop section. When the elongate rod is released from the actuation of the angled fixture, the resilient means bias the movable wedge towards the fixed wedge and the elongate rod is displaced upwardly in the passage. The inclined surface of the movable wedge is engaged with the inclined surface of the fixed wedge and the resilient gripper engages the movable shaft member and retain the movable shaft member to lock the adjustable tabletop section on a desired height.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of the table in its normal position.

FIG. 2 is a side view of the sofa table of the present invention.

FIG. 3 is a side view of the table in its height-adjusted position.

FIG. 4 is a detail of the adjustable strut.

FIG. 5 is a detail of the mechanism involved when it is in the un-locking mode, whereby the movable top is released to be freely adjusted for the desired height.

FIG. 6 is a detail of the mechanism involved when it is in the locking mode, whereby the movable top is locked at the desired height.

FIG. 7 shows the side view of the strut of the second embodiment of the present invention.

DETAIL DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention is a sofa table having a top or a portion of that top which can be elevated and to be used as support for eating and writing. FIG. 1 illustrates the horizontal top of the table preferably comprising at least two table top sections (1, 2). At least one of the sections can be elevated to a higher level with the attachment of an adjustable means at the bottom of the table top. The table top sections (1, 2) can be of arbitrarily formed or combined as a single piece to accommodate the final design preference and requirements.

In the first embodiment of the present invention as shown in FIG. 2, the table top is supported by a leg frame assembly (4). A height adjustable strut (6) has one end pivotally mounted at the adjustable section (2) of the table top at a first mounting point (8), and the other end pivotally mounted to the lower part of the leg frame assembly (4) at a second mounting point (7) unto the leg means which is connected to the stationary section (1) of the sofa table, acting like an inclined strut supporting load from the adjustable section of the table top. The height adjustable strut (6) pivoting location on the adjustable section (2) of the table top is best at a proximity whereby the height adjustable strut (6) can provide the equilibrium support to the table top at any height, more than one of such means can be pivoted at equidistance to share the load if stronger support for the table top is required. The pivoting locations for both ends of the height adjustable strut (6) are critical because these will determine the balancing performance of the table. If the adjustable section (2) of the table top is extended too far away from the center axis of the table, it is more susceptible from being toppled due to moment of force; if weights or downward pressure caused by objects placed on the table top are not equally spread out.

In another words, any moments of force born by one side of the table has to be equilibrated by collective weights of the other side in order to ensure a well-balanced table. In one embodiment, the adjustable height adjustable strut (6) can be operated either mechanically or electrically, for example those mechanism that could provide upward and downward movements like piston and cushion, pneumatic cylinder, tube and rod, threaded cylindrical rod are all could be used. For the mechanism that is electrically operated, an on board battery is needed in order to supply the power needed to the strut (6). However, the latter design is not so favorable as motor as well as the battery have to be periodically serviced, therefore indirectly will add extra burden to the cost.

FIG. 3 illustrates a side view of the adjusted sofa table, whereby the extendable support member of the sofa table includes an elongated supporting arm (40) fixed at the bottom surface of the adjustable section (2) of table top in an incline position. The elongated supporting member has a first support member comprising a first elongated arm (40); and a second support member (9) comprising a second elongated arm in a sliding relationship with the first elongated arm. For example, the second elongated arm is slidably engaged in a receiving slot which is a hollow bar or hollow arm (9) having an opening at the upper end and the lower end mounted at the stationary side of the leg means in a corresponding incline position preferably at the point nearby the second mounting point (7). This is to improve the slidability of the adjustable section (2) of the sofa table as well as to provide extra balance and support to the table top. In addition, the supporting member (40) could also include the utilization of roller and railing system in order to further assist a smoother sliding upwards and downward movements of the adjustable section (2) of the sofa table. In addition, extra members incorporated unto the side of the table are also intended to counterbalance those extra moment of force created by the extended table top portion to avoid the table from being toppled.

FIG. 4 illustrates the details of the height adjustable strut (6) and all its components. The height adjustable strut (6) itself includes two parts; a stationary member (10) which is pivotally connected to the lower part of the leg frame assembly (4) at the second mounting point (7) unto the leg means which is connected to the stationary section (1) of the sofa table. A movable member (11) has one end connected to the adjustable section (2) of the table top which can be slid along the stationary member (10). This movable member (11) is responsible for the height adjustment of the sofa table. The movable member (11) can be made of any material that is strong enough to provide a rigid structural support to the table top. In one embodiment, the movable member of the adjustable strut is in a sliding relationship with the stationary member and the movable member will engage the stationary member in a locking position when the locking mechanism is engaged to allow the table top to adjust to the desired height. In another embodiment, the locking mechanism which is not shown here, is selected from the group consisting of spring load hook, mechanical height controlling fixture or mechanical lever, to engage and disengage the movable member of the adjustable strut to extend or collapse. The main purpose of the locking mechanism is to provide a means to hold the adjusted table top into a desirable height and is able to maintain and lock the desirable height in place. The following paragraph and description provides an exemplary assembly and component member works collectively to provide an extendable assembly for supporting an adjustable height sofa table.

As an example, for a more detailed description of the sliding mechanism, the height adjustable strut may further includes a sliding inner tube (18) slidable within the outer tube (11) and a controlling fixture (13) which includes a tapered inner bore that receives compressible tapered portion (12) and a resilient means (14) with one end mounted to the compressible tapered portion (12) and the other end mounted to the end of the outer tube (11) which is adjacent the second mounting point (7). The inner tube (18) is slidable within the outer tube (11) feature looks like a commonly known device such as a telescopic device which also has a similar combination of elements assembled together to provide a similar function. The narrower part (15) of the compressible tapered portion (12) is engaged with the stationary rod (10) as a stopper when in released position. This narrower part (15) of the compressible tapered portion (12) is engaged with one end of the sliding inner tube (18). The resilient means (14) used in a preferred embodiment is a spring. The controlling fixture (13) is incorporated unto the adjustable strut to allow the adjustable table top section (2) of the sofa table to be locked at any desired level within the range of the allowable height. A lever (17) loaded with resilient means (not shown) is pivotally mounted at the bottom surface of the adjustable table top section (2) adjacent the first mounting point (8) to engage and disengage the controlling fixture (13) along the adjustable strut (6).

The working principle of mechanism that enables the height adjusting is shown in FIGS. 5 and 6. The adjustable section (2) of the table top can be raised when the angled lever (17) is engaged and pressed against the sliding inner tube (18) in the downwards direction to release the locking mechanism of the controlling fixture. The spring (14) of the controlling fixture (13) that is located in the other end of the movable outer tube (11) thus compressed by the downward pressure and the compressible tapered portion (12) of the controlling fixture (13) compressed and the locking mechanism hence is released or disengaged, therefore enable the movable outer tube (11) to slide along the stationary rod (10).

Once the angled lever (17) is released, the downward force is withdrawn, thus causing the initially compressed spring (14) to push back the sliding inner tube (18) in the opposite direction and subsequently cause the compressible tapered portion (12) to be uncompressed and engaged with the movable outer tube (11) and grip tightly unto the movable outer tube (11) for locking the table top at the desired position. Other suitable locking mechanism of the strut (6) can also be used.

FIG. 7 shows another embodiment of the locking mechanism for the extendable assembly (6) of the sofa table. The extendable assembly (6) includes a stationary member (20) having one end connected to the lower part of the leg frame assembly (4) at the second mounting point (7) unto the leg means which is connected to the stationary section (1) of the sofa table and a movable member (21) having one end connected to the adjustable section (2) of the table top, whereby the movable member (21) having the bottom surface slidably engaged with the top surface of the stationary member (20). The stationary member (20) includes a channel (27) along the length of the stationary member (20) and a housing having a fixed wedge (28) at the inner bottom of the housing to accommodate a controlling fixture (23). The controlling fixture (23) has a corresponding movable wedge (29) with an elongated rod (26) mounted through the entire length of the movable wedge (29). The elongated rod (26) slidably extends through a through hole formed at the fixed wedge (28).

The movable wedge (29) is slidably engaged with the fixed wedge (28) of the housing. The elongated rod (26) comprises a resilient means (24) which is a spring having one end connected to the wider part of the movable wedge (29) and the other end with a stopper (25) which is a washer to prevent the spring (24) further pushed out of the housing into the channel (27). The top surface of the movable wedge (29) has a resilient gripper (30) attached to the top thereof. An angled lever (17) is provided at the bottom of the adjustable section of the table top. The angled lever (17) is biased by a resilient means and is pivotally mounted at the bottom surface of the adjustable table top section (2) adjacent the first mounting point (8) to engage and disengage the controlling fixture (23) along the adjustable strut (6). The angled lever (17) is rotatably mounted and can be engaged or disengaged whereby an extended tip of the angled lever (17) would actuate the elongated rod (26) in a downward direction in the embodiment of FIG. 7.

The working principle of the locking mechanism for the second embodiment is almost similar with the first embodiment of the sofa table. An angled lever (17) is rotatably engaged with the other end of the elongated rod (26) that enables the height adjusting of the table top. The adjustable section (2) of the table top can be raised when the angled lever (17) is engaged and pressed against the elongated rod (26) in the downwards direction. The movable wedge (29) is pushed towards the spring (24) and thus the controlling fixture (23) lowered and the locking mechanism hence is released or disengaged, therefore enable the movable member (21) to slide along the stationary member (20). When the angled lever (17) is disengaged with the elongated rod (26), the spring (24) will push the movable wedge (29) and thus the movable wedge (29) is raised against the fixed wedge (28) to enable the resilient gripper (30) to engage with the movable member (21).

In another example to illustrate further the working principle of the locking mechanism, if a force is appeared to be applied to the table top, the force would not be transferred down to the movable member, whereby when the elongated rod (26) is in the released position, the spring, attached at the wider part of the movable wedge (29), tends to stretch back to uncompressed form causing the movable wedge (29) to be actuated towards the fixed wedge (28). Since the movable wedge (29) is being stopped by the fixed wedge (28) before the spring could stretch back to its normal uncompressed form, the movable wedge (29) is firmly gripped in a rigid position as the spring tends to stretch but the pushing force from the spring is being held back by the movable wedge (29). This causes the the movable member to be retained rigidly and would not slide along the resilient gripper. The resilient gripper provides traction force that fully disable any sliding downward force to let the movable member to slide. Unless the resilient gripper is released from its grip from the movable member, the movable member will slide. If a force is imposed on the table top, the downward force on the movable member would be in a balance manner retained by the traction force implemented by the resilient gripper. The resilient gripper works like a brake. The more downward force is imposed on the movable member, the resilient gripper would impose more traction force to grip the movable member.

In another embodiment of the present invention, the movable wedge (29) is formed without the resilient gripper (30) but provided with an additional vertical plate (not shown) partially incorporated at the rear part of the movable wedge (29) as a protrusion to engage with the bottom surface of the movable member (21) for adjusting said adjustable section (2) of the table top at any desired level within the range of the allowable height. The working principle of the locking mechanism for the third embodiment is similar with the locking mechanism of the second embodiment of the sofa table.

Preferred and alternate embodiments of the present invention have now been described in detail. It is to be noted, however, that this description of these specific embodiments is merely illustrative of the principles underlying the inventive concept. It is therefore contemplated that various modifications of the disclosed embodiments will, without departing from the spirit and scope of the invention, be apparent to persons skilled in the art. For instance, it is obvious the one skilled in the art of the present invention that alternate embodiments of the present sofa table can include different shape and means of extendable mechanism. 

1. An extendable assembly for supporting sofa table comprising; an extendable support member having opposing first and second support ends, a height adjustable strut having opposing stationary and movable members, a spring loaded locking mechanism coupled to the adjustable strut for locking the adjustable strut at a desirable distance, wherein the stationary member of the strut is coupled to the bottom section of a leg member of the sofa table and the movable member of the strut is coupled to the bottom surface of the top face of the sofa table, wherein the movable member of the strut may be moved toward and away from the stationary member when force is applied, wherein the extendable support members respectively collapse and extend in response to the application of force.
 2. The assembly of claim 1, wherein the extendable support member comprises: a first support member comprising a first elongated arm; and a second support member comprising a second elongated arm in a sliding relationship with the first elongated arm.
 3. The assembly of claim 1, wherein the movable member of the adjustable strut is in a sliding relationship with the stationary member, the movable member will engage the stationary member in a locking position when the locking mechanism is engaged to allow the table top to adjust to the desired height.
 4. The assembly of claim 3, wherein the locking mechanism is selected from the group consisting of spring load hook, mechanical height controlling fixture or mechanical lever, to engage and disengage the movable member of the adjustable strut to extend or collapse.
 5. An extendable assembly for supporting sofa table comprising: a stationary strut member mounted in an inclined manner to a sofa table, wherein the bottom end of the stationary strut member is coupled to the bottom section of a leg member of the sofa table and top end of the stationary strut member is coupled to the bottom surface of the top face of the sofa table, the stationary strut member has a hollow a passage and a fixed wedge attached at a predetermined position in the passage, the fixed wedge is disposed such that an inclined surface is formed facing upwards; a movable shaft member slidably coupled to the stationary strut member, wherein the top end of the movable shaft member is coupled to the bottom surface of the top face of the sofa table, the bottom surface of the movable shaft member is slidably mounted on the top surface of the stationary strut member; a controlling fixture having a movable wedge positioned relatively at the bottom of the fixed wedge, wherein the movable wedge is disposed such that an inclined surface is formed facing downwards and engageable with the inclined surface of the fixed wedge, the movable wedge has a resilient gripper attached to a top surface thereof, the resilient gripper on the top surface facing towards and engaging the bottom surface of the movable shaft member; an elongate rod slidably mounted through a through bore formed at the fixed wedge, wherein the bottom portion of the elongate rod is fixedly mounted through a through hole formed at the movable wedge; a stopper is disposed at the bottom section of the stationary member, the stopper terminates the passage of the stationary member; a resilient means is attached at the bottom end of the stopper and attached at the top end to the movable wedge; and an angled fixture mounted to the top section of the opposing leg member, the angled fixture arranged to actuate the elongate rod and move the movable wedge towards the stopper; when the elongate rod is actuated by the angled lever, the movable wedge is forced to move downwards and the resilient means is compressed, the resilient gripper is released from its engagement with the movable shaft member and allows the sliding of the movable shaft member that facilitates the adjustment of height of the adjustable tabletop section; and when the elongate rod is released from the actuation of the angled fixture, the resilient means bias the movable wedge towards the fixed wedge and the elongate rod is being displaced upwardly in the passage, the inclined surface of the movable wedge is engaged with the inclined surface of the fixed wedge, the resilient gripper engages the movable shaft member and retain the movable shaft member to lock the adjustable tabletop section on a desired height.
 6. The height-adjusting device for a sofa table according to claim 5, wherein the angled fixture is operated by a resilient member to actuate the elongate rod.
 7. The height-adjusting device for a sofa table according to claim 5, wherein the resilient means is a spring.
 8. The height-adjusting device for a sofa table according to claim 5, wherein the resilient gripper is made of elastic material capable of gripping the movable shaft member when the resilient gripper is engaged to the movable shaft member. 